Fungicidal and bactericidal compositions



Patented May 1945 moron). AND BACTEBJUIDAL comosrrross with x. Bellman, manna, Mich, assignoi' to The Dow Chemical Company, Midland, Mich, a corporation of Michigan No Drawing. Application December 28, liiil', Serial No. 424,477

Claims.

The present invention is concerned with fungi cidal and bactericidal compositions and particu larly with such compositions comprising as an active toxicant a mixture of phenolates.

According to the present invention, it has been discovered that when alkali metal salts of pentachlorophenol and of 2 phenyl-monochlorophenol are mixed together, compositions are ob.- tained which exert a fungicidal and bactericidal action greatly in excess of that predictable from a knowledge of the eflectiveness of the component phenolates. The proportions of materials employed vary somewhat with the use for which the composition is designed and the particular salts concerned. Generally, from ill to 100 parts byweight of the alkali metal salt of Z-phenyimonochloro-phenol is used for each 100 parts of the alkali metal pentachlorophenolate.

The compositions of the invention may be prepared by grinding or otherwise mixing the 2- phenyl-monochlorophenolate and pentachlorophenolate'to obtain finely-divided solid products adapted to be dissolved in water or other suitable liquid carrier.; In an alternate procedure; a mixture oi the free phenols may be treated with aeous alkali to form liquid phenolate products adapted to be either evaporated to dryness and around, or employed for a fungicidal and germicidal control as obtained or after modification with additional liquid diluent.

Mixtures of the sodium salts of pentachlorophenol and of 2-phenyl-monochloro-phenol constltute the preferred embodiment of the present invention, although other salts such as the potassium and lithium salts or mixtures of sodium. potassium, and lithium salts may be substituted therefor. The commonest form in which the 2- phenyl mono-chloro-phenolate is employed is as a mixture comprising from '10 to 80 per cent by weight of the ortho-chloro isomer and the bal ance principally the para-chloro isomer. with only'a trace of the meta-chloro compound. This mixture is obtained by forming the alkali metal phenolate from the phenol mixture resulting from the direct chlorination of -2-phenyl-phenol.

If desired, however, pure z-phenyl-fi-chloro .phenolate, 2-phenyl-5-chloro-phenolate, or 2- phenyl-4-chloro-phenolate may beemployed.

The phenolate mixtures have been found" superior to either the pentachlorophenolates or 42-phenyl-monochlorophenolates alone as regards the fungicidal and bactericidal controls accom-' plished in such representative fields as the treatment .of freshly sawn lumber for sap stain control, mold-proofing of canvas and other rough fabrics, preservation of cordage, etc, In such operations aqueous solutions comprising from.

about 4 to about pounds .of to'xicant per 100 gallons (U. S.) are employed. The treatment of a complished eitherby dipping or by pressure impre'gnation; In pressure impregnation of wood.

the treatment also serves to protectthe cellulosic structure irom'attack by termites.

5 Similarly,. the pheno'late mixtures have been found effective in the preservation of paper and specifically in the mold proofing oi egg case flats and fillers. For this use lrornabout Otto 0.5 per cent by weight on a dry basis of the phenolate mixture is incorporated with the paper pulp dur ing the beating step. The paper product made from the treated pulp is resistant to mold growth even under conditions of high humidity, and as in the case oi egg flats and fillers, may exert a desirable iungistatic eiiect upon food products wrapped or packed therein.

A iurther development in which the composition oi the present invention has been found particularly effective is that of slime and algae control. From 2 to 10 parts of the phenoiate mixture per. million parts of water prevents the growth oi algae and slime organisms in the water systems oi paper mills humidifier and boiler installations, cooling towers, etc. In such application a mixture of 60 per cent by weight pentachlorophenolate-dll per cent by weight fi-phenyl- A series of determinations were carried out to ascertain the eii'ectiveness of a mixture of sodium pentachlorophenolate and sodium 2 phenylmonochloro-phenolate (the ortho-para mixture) against a number of representative organisms.

The particular product employed consisted of a mechanical mixture of 80 parts-by weight oi the sodium pentachlorophenolate with 40 parts by weight of the 2-phenyi-monochloro-phenolate. Control determinations were made with sodium -pentachlorophenolate alone. The following table sets forth the results obtained in terms of parts by weight of tomcant per million parts of water required to kill the test organisms employed.

. Partspermilliontokill with- Organism Muted phenolates Bumble 2 A mixture, of 40 parts by weight or sodium 2- .phenyl-monochloro-phenolate and 30 parts 01 sodium pentachlorophenolate was modified by the inclusion of 30 parts by weight of sodium 2.3.4.6- tetrachlorophenolate. This mixture or toxicant materials was tested according to the well known agar plate method to determine its efficiency against such common wood stainers and destroyera as C. pillifera, H. gelattnosum, and L. trabea. Sodium pentachlorophenolate alone was employed as a control material.

The phenolate mixture was found to completely inhibit and kill C. pillijera at a concentration of between 0.0035 and 0.005 per cent by weight. Sodium pentachlorophenolate inhibited and killed this organism at a concentration of between 0.005 and 0.007 per cent.

Against H. geiatmosum, the phenolate mixture gave complete inhibition and kill at between 0.0025 and 0.010 per cent. With sodium pentadispersing agents. For example, inorganic and organic mercurials, 'borax, dinitrophenols and their salts, and water-soluble salts of sulfuric acid derivatives of alcohols, phenols, aromatic hydrocarbons, etc. may be incorporated into the phenolate mixtures, if desired, provided only that such addition agents not enter into chemical reaction with the phenol salts.

I claimi 1. A flmgicidal and bactericidal composition comprising as an active toxicant a mixture oi! the alkali metal salts of pentachlorophenol and of 2- phenyl monochlorophenol.

2. A fungicidal and bactericidal composition comprising as an active toxicant a mixture of from 10 to 100 parts by weight oi sodium 2-phenylmonochloro-phenolate with 100 parts of sodium pen tachlorophenolate.

chlorophenoiate, between 0.010 and 0.020 per cent was required to give inhibition of growth, and between 0.020 and 0.035 per cent to kill the orenism.

Against L. trclrea, the phenola'te mixture gave total inhibition and hill at a concentration of between 0.001 and 0.002 per cent. With sodium pentachlorophenolate, the concentration required to give total inhibition was between 0.002 and 0.0030. A concentration of between 0.0035 and 0.005" was required to kill the organism with the sodium pentachlorophenolate alone.

The compositions as hereinbefore described comprise the mixture of phenolates as the principal active toxicant but may be modified by the addition of other toxicants, or wetting and 3. A fimgicidal and bactericidal composition comprising as an active toxicant a mixture of from 10 to 100 parts hyweight of an alkali metal salt of 2-phenyl-monochlorophenol with 100 parts by weight of an alkali metal salt of pentachlorophenoL 4. a fungicidal and bactericidal composition comprising as an active tomcant a mixture of from 10 to 100 parts by weight of sodium 2- phenyi-monochloro-phenolate with 100 parts by weight of a mixture of sodium pentachlorophenolate and sodium tetrachlorophenolate.

5. A fungicidal and bactericidal composition comprising as an active toxicant a mixture of 00 parts by weight of sodium pentachlorophenolate and parts of sodium 2-p-henyl-monochlorophenolate.

DONALD K. BAILMAN. 

